Intermittent movement mechanism



Feb. 20, 1951 T. F. HARVEY 2,542,515

INTERMITTENT MOVEMENT MECHANISM Filed June 14, 1949 4 Sheets-Sheet 1 FIG. 5 FIG. 4

U E q INVENTOR: THADDEUS F. HARVEY ATT'YS Feb. 20, 1951 T. F. HARVEY INTERMITTENT MOVEMENT MECHANISM 4 Sheets-Sheet 2 Filed June 14, 1949 gig f I7 II "m l 1 INVENTOR; THADDEUS F. HARVEY AT T'YS Feb. 20, 1951 T F RVE 2,542,515

INTERMITTENT MOVEMENT MECHANISM Filed June 14, 1949 4 Sheets-Sheet 5 INVENTOR:

THADDEUS F. HARVEY ATT'YS Feb. 20, 1951 F, HARVEY 2,542,515

INTERMITTENT MOVEMENT MECHANISM Filed June 14, 1949 4 Sheets-Sheet 4 FIG. H

DWELL INVENTOR: THADDEUS F. HARVEY ATT' YS Patentecl Feb. 20, 19 51 IN TERMITTEN T MOVEMENT MECHANISM Thaddeus F. Harvey, South Bend, Ind., assignor to Bodine Electric Company, Chicago, 111., a corporation of Illinois Application June 14, 1949, Serial N0. 98,905

10 Claims.

This invention relates to devices for imparting intermittent movement to a driven mechanism and particularly to such devices which, while driven by a constant speed or continuously moving power source, will operate only at predetermined intervals.

The main objects of this invention are to provide an improved mechanism for causing intermittent operation of a driven mechanism; to provide such a device which will operate at exactly timed intervals in the driving cycle; to provide such a device which will impart exact predetermined increments of angular movement in a driven mechanism; to provide an improved rotary intermittent movement mechanism which will operate quietly and smoothly regardless of the load transmitted through the mechanism; to provide such a device in which the intermittently moving elements are accelerated and decelerated with the smoothness and exactitude of a simple harmonic motion; and to provide an improved intermittent movement mechanism of a simple rugged construction that will transmit relatively heavy loads through exact increments of angular movement regardless of the speed of operation of the mechanism. 1 Other objects are -to provide an improved rotary intermittent mechanism which may be constructed in substantially any size without loss of accuracy initsoperation; to provide: such a mechanism which may be built to transmit relatively heavy loads without loss of accuracy or efficiency in its operation; and to provide such-a mechanism that is readily adaptable to substantially any apparatus wherein an intermittent rotary action is desired.

Intermittent movement mechanisms, generally, .are well known and are employed in many difier-f lent environments and kinds of apparatus, some of which require a high degree of accuracy of op- .eration particularly with respect to registry of the driven part with some other coacting device. -It.is for apparatus requiring accuracy of operation of the driven element that the present in- '-vention was devised and while specific applications of the invention are herein shown and described it is to be understood that the use of .the invention is not intended to be limited to such applications. Rather the invention is intended for usein any situation in which an intermittent iii 2. tion, showing the improved intermittent move-- ment device embodied in the variable stroke span control mechanism of a machine for wind ing the stators of electric motors.

Fig. 2 is a diagram illustrating the nature'of the intermittent movement in the driven mechanism as provided and controlled by the device of Fig. 1. V Fig. 3 is a diagrammatic view showing the end of a stator and illustrating a coil winding problem requiring a high degree of accuracy and control in the winding machine and for which the improved intermittent movement device is particularly suitable." Fig. 4 is a diagrammatic view showing the dc"- veloped windings of a typical four pole stator and illustrating the type of Work that may be done by the mechanism of Fig. 1.

Fig. 5 is a diagrammatic view illustrating the stroke and span operations of the winding machine, the span movement being the operation performed and controlled by the intermittent movement device of Fig. 1. v Fig. 6 is a plan view of a stator winding ma chine span operating mechanism embodying" the improved intermittent mechanism.

Fig. 7 is a view of the same in side elevation. Fig. 8 is an end view of the same as seen from the line 88 on Fig. 7.

Fig. 9 is a view of the driving gear and pinion for the intermittent device, as taken on line 99 of Fig. 1, showing the pinion arrangement for permitting a predetermined dwell in the intermittent operation.

Fig. 10 is an end view of the intermittentdevice-showingthe manner of engagement of the bearing elements and the control cam.

Fig. 11 is a top plan view of the control or operating cam for the intermittent device.

Fig. 12 is an enlarged fragmentary side view of the control cam showing the form and arrangement of the operating cam surfaces by which timing and control of the intermitten device is obtained, and i Fig. 13 is a schematic perspective view showing :the intermittent device embodied in the film transport mechanism of a motion picture ap- ;erating and control mechanism of an automatic stator winding machine, such a mechanism being a particular example of a situation where great accuracy of operation is an essential factor for efiicient high speed production; and Fig. 12 shows the intermittent device as it may be embodied in a motion picture apparatus. These examples of application of the invention serve to illustrate the adaptability of the invention to mechanisms having widely different speed and load factors and space or size considerations.

As shown in Figs. 1 to 11 inclusive the intermittent device is particularly arranged to operate and control the span operation of the wire gun, of a stator winding machine, which element, though not shown, will be understood to be the device which threads orleads the winding wire through the required path to jiqr-m the windings on the poles of a stator. As is well known, in the stator winding machine art, the

4 tricity of the crank pin 6 relative to the axis of the intermittent shaft 1.

As will be later described, the gear teeth on the pinion l are interrupted at predetermined locations, as shown in Fig. 9, so that though the gear II rotates continuously, the shaft 1 will be turned only when the teeth on the pinion l0 engage the gear I I, and will stop whenever the interrupted tooth portions of the pinion ll) become radially aligned with the gear II. This action is substantially the same as that obtained 'irom'the old and well known Geneva type of movement and the crank in 6 will be driven only y "when "the teeth 'of the pinion are meshed with the ear] I, thereby imparting an intermittent reciprocating motion to the connecting rod wire gun is a reciprocating element which oscillates at the end of each stroke to lead the windlng wire angularly across the span between 'the stator pole slots. The "extent of this angular movement tr turn 6f thewir'e (gun "during its oscillation'fiiust be very accurately con'tl'blled "to obtain roper "augment with 'therespec'tive stator slots so that on the neirt"axial"stroke of 'fthelwi're gu'n'the winding wire will be accurately positioned in the "slot. This is the function of the intermittent "devise.

Referring particularly to Fig. 1, the rifaincatfrier or support for the wiregunis indicated by 'theiiumerai l "andis'u's'li'ally a 'tubularmember fotata'bly 'ihounted 'ih fixed bearings, fa reciprooable wife'gun shaft 2 is 'fsli ilably mounted Within the tubular carrier I andiskeyed the carrier for rotation therewith, and the' e gun not shown, is mounted on the end 'of the "Shaft 2 which" projects 'b'ydiid the end of "the carrier 1, The shaft Tisdcltiitdlfi inearisjifdtslidwh, to cause the wire gunlto pass ibackfjand ,iforth "aria-11ythrou h the center 'opeiiing or a stator .to'efiec't the stroke movements eithewire "gun; :ahd the carrier fl "is estimated ih' liv lideterniiried tlfiie d relation with tile strtke movements of; the shaft 2 to oscillate the wifeigun an iuariy, between "strokes, to elfect the 'spanimdvemexa .of the wire gun.

.The oscillation attention er'ftiie earrri in "is;

lotitained by means "or a reciprocable rack 3 which is suitably inou nted in slide-ways, not shown, and arranged to engage agearl fixedly mounted on the carrier member l, The rack 3 -re,oiprocated linearly to eflect mutation of the gear 4 and the carrier1memher ;l, -by means of connecting rod 5 which is mounted on a crank ,pin 6 which in turn is driven by theinter-mit- I tent .:-mechan is.n 1. As indicated in Fig, the

driven end of theyconneoting rod SrjlS suitably jonrnaled on thecrank pin -,6 rand its opposite end is formed with a 'cl'evis ;-for pivotal connection "with the rack .3. v,

' The intermittent. :device which drives the crank'pin 6 and the aconnectingirod 5,1:omprises ahollow shaft 1, rotatably:mduntedaina pairof fixed bearings 8 and 5. This :shait-ca rries a-fixed pinion 10 which in turn is meshed 'with'adriv- :ing gear ll mounted-fast-on a shaft l2; and the gear H is driven by a constant speed power source, not shown. The crank pin 6 is e'ccerritri'cally mounted on bne endto'f the intermittent shaft 1 and *as the sha'ft is driven by "the gear and pinion, "I l and it respe'ctiii'ely," the'cennect- 1m rod't is caused :to reciprocate to drive the rack 3 "which in turn rotates the carrier tliioiigh predetermined inerements of "angular amine task -:3.' The pinion and gear are not, however, self-engaging, as in the case of a Geneva movement and additional means for that purpose must be provided.

The means for causing engagement of the 'te'ethon-the pinion Hlwith-the ear II at predetermined timed intervals, and for holding the intermittent shaft 1 stationary whenever the interrupted toothed portions of the pinion [B are tangential with the gear l b-is located at the opposite end 'of the shaft 7 from the driven means -or crank pin 3, and, as shown, comprises a hub or head I 3 integral on the "shaft 1 and carrying a pair of outwardly projecting bearing elements 14 and 15, which are located at diametrically opposite posit-ions on'the head 1'3. :In "the Torin shown, the bearing elements are disposed with their axes projecting outwardly from the head l3, at an angle relative to -'the axis of the-shaft '1, and-extend into the path of'a-rotary cam 15, which is a specially designed device adapted to successively engage the "bearing elements M and T5, and hold "them successively 'in a "fixed position for a predetermined time and thenrel'ease'them inshch a manner as to cause suflicierit rotation of "the "shaft 1 to effect engagement of the teetho'nthe pinion Ell] with the gear H. The-particularconstruction-of"the controlcam "l6 will=be hereinafter described'in detail.

- As shown, the oam I6 -is driven at a constant speed-by a sh'aft 11 which in turn is driven by meansofa connection, not shown, from the shaft 2 and the "source of the *power'there'for. *Thus the gear 1 l =-'andthe cam FE operate in timed'r'elati'o'n andthe gear will driveth'epinion l0 and tl'i'eshaft *1 only when the bearing elements H and 1 5 arereleased fro'm the cam l6; and during the period that the'bearingelements M'and l5 are engaged with the cam 4'6, the intermittent shaft 1 will be held -s'ta-tionary, without any possibility of backlash or override in the angular movement of the crank pin "6, so that only the exact predetermined arnourit of rotationof the wire gun-carrier I will occur toffec't the angular or s'pa'n rnovement *of the wire gun.

This exact predetermined angular movement of'thegun and theperiod 'of dwell, or the period 'w'h'erethe angular-position of the wire'gun must be held stationary, is illustrated by the diagram of Fig. 2which shows the periods of angularmo tion and dwell'o'fthe wire gun during one cycle of its'operation. Thus the'wi're gun cycleybeginning at -the point :cinthddiagram of Fig. 2, first comprises-a strokewh'ich occupies the dwell period of the intermittentoperation, then a turn through a predetermined increment of angular movement under 'the operation of the intermitmovement according to "the amount-"0'1 'eqcmtent-device, the'nase'cond'or return'stroke during a dwell period of the intermittent device, and finally a second turn through the predetermined increment of angular movement upon the next operation of the intermittent device. Since the stroke movements of the wire gun must be made while the wire gun is held fast against any angular movement, and since the extent of the angular movement of the wire gun to effect its span operation must be precisely a predetermined amount, it will be seen that the intermittent de- .vice must be capable of a very high degree of accuracy in its operation.

In order to illustrate the operations of a stator winding machine for the control of which the improved intermittent movement device is particularly adaptable, reference is made to Fig. 3 which shows an end view of a typical four pole stator; and wherein each pole is to be provided with two separate coils or windings which are formed about a common center. The wire gun which forms these windings is usually designed to wind diametrically opposite poles simultaneously and in winding the poles the desired number of turns are first placed in the slots comprising the center coil and then the span of the ,wire gun is shifted to wind the second or outer coil of the pole. When the second or outer coil -is completed, the stator is indexed through a predetermined angular turn and the coils are then wound about the intermediate poles.

The slots indicated by represent the pole centers and in the winding operation, the wire gun on its first stroke through the stator lays the wire in the slot .l-E. The wire gun is then ,turned angularly through the span to an alignment with the slot IL and, after the span has been made, the wire gun performs its second ;stroke through the stator in the opposite direc- ;tion of the first stroke and lays the wire in the slot IL. The wire gun is then turned in the reverse direction through the span distance and, upon ceasing rotation, makes another stroke through the stator to again lay the wire in the slot l-E,- after which the wire gun turns through vthe span distance and returns through the stator ;to lay the wire in the slot I L.

This operation is continued until the desired 1 number of turns have been laid in the slots for .the inner coil, after which the span distance or angular movement of the wire gun is automatigcally adjusted for the spacing of the slots of the second or outer coil and the winding operation is continued, the wire being laid through the slot 2-E on the first stroke of the wire gun and returned through the slot 2-L on the second or return stroke of the wire gun after it has passed vthrough the span distance. The winding operation is then continued until the second or outer vcoil has been provided with the desired number ofturns at which time the stator is indexed .for. the winding of the intermediate poles. The intermediate poles are wound in the opposite ,direction of the first poles as indicated in the diagram of Fig. 3 and for this operation, the sequence of movements of the wire gun are reversed. The mechanism for effecting the reverse winding operation of the wire gun forms no part ,of the present invention, and therefore, need not be discussed.

Fig. 4 shows the winding of a four pole statorin developed form and indicates the path of the wire as it is laid around the poles and through the pole slots by the wire gun. The north poles .are wound simultaneously and then, after the tator isind xed and the winding mechanism is reversed, the south poles are simultaneously wound. After the winding of the coils has been completed the appropriate ends of the wires are connected together so that the several coils will be connected together in series, as will be readily understood. The difiicult factor, however, in the winding operation is the accurate alignment of the wire gun with the pole slots since the pole slots are relatively narrow as indicated in Fig. 3, and unless accurate alignment of the wire gun with the slots is had, wire breakages are bound to occur. Thus the span operation of the wire gun mustbe controlled with a high degree of accuracy, and it is this accuracy of control that the intermittent device affords.

As before mentioned, the span movement of the wire gun is variable through adjustment of the eccentricity of the crank pin 3 relative to the axis of the intermittent shaft 1, such adjustment being the means by which the span of the wire gun is shifted to form the windin s of the outer coil after the winding of the inner coil has been completed. The span distance for the outer coil is double that for the inner coil in the particular stator illustrated in the Fig. 3. Thus, as embodied in a stator winding mechanism, the inter-- mittent device includes means for automatically changing the span distance, or increment of angular rotation of the Wire gun carrier l, upon the completion of the winding of one coil. This span change mechanism forms no part of the presentinvention-v and will, therefore, only be briefly referred to;

As shown in Fig. l, the crank pin end to the intermittent shaft 1 is provided with a relatively large head I3 in which a hollow slide. [9 is mounted in suitable slide-ways, for radial movement relative to the axis of the shaft 1. The crank pin 3 is mounted fast on this slide l5 and the amount of eccentricity of the crank pin determines the span distance. The position of the slide it, radially relative to the axis of the shaft 1, is controlled by a rack 29 having teeth on opposite faces which are disposed at an angle of 45 degrees relative to the axis of the shaft 1. The rack 23 is mounted on the end of an operating shaft 2| which extends centrally through the hollow intermittent shaft i and projects outwardly beyond the control head or hub IS. The hollow slide I9 is provided with rack teeth on its inner surfaces arranged to mate with the teeth and the teeth formed on the inner surfaces of the slide I 9, the slide it! may be caused to shift radially relative to the axis of the intermittent shaft 1 merely by changing the position of the rack 20 axially in the crank head I8.

This shifting of the rack 20 is accomplished by means of a cam 22 which is arranged to enage a roller 23 on the outer end of the shaft The cam track 24 of the cam 22 is eccentric to the axis of the cam 22, and thus, by rotation of the cam, by a suitable means not shown, the rack shaft 2| can be caused to shift axially in the intermittent shaft '1 so as to vary or change the eccentricity of the crank pin 6. It will be understood that the rack shaft 2| is keyed to rotate with the intermittent shaft 1 and that, therefore, the extension '25, which carries the roller 23 and which thus does not turn, is rotatably connected end to end with the shaft 2|.

Referring to the specific embodiment of the invention, in the span control mechanism of a 76- stator windingmachine, shown in Figs. 6, 'land "panama 8, it he :seen that the intermittent device is tassembledpas aimorev pr less independent strucictura on' a base or platform '30, with the inter- :mittentrshaft Fl :dispos'ed'horizontallysat'the upper epartnf the structure'zand mounted in the bearlings: 8 and '9, which arein turn supported in lbos'ses :formed' on upstanding wall-like members :31 and :32, :respectiveiy, which are -integral with the i'base 53D.

Thedriving :end'iof the shaft 7' projects outwardlyiirom the hearings and the acrankhead ill] is located on theoutsideaof the bracket 32 where "it isifree and clear-Jim operation iof the connect? i ingrod l5,- which extends Elaterally :from the intermittent unit for connection to -the wire gun g;-

.unit, as :indicated in 'l.

The controlled tend 10f the "shaft ilproiects he fyond the bearingiia into 2a spacewhere-ithecontrol 'head 213., together with its iangula'rly projecting -'.bearing'elements, l4 and Ll=5,t may rotate -without interference, "except as -'such:rotation*is controlled by the control :cam 15. The control cam lfi is mounted fast on the upper end of the shaft 1H, zwhich'is disposed at'right anglesto the intermittent :shaft 1, andthe shaft I?! is journaled in -spacedtbearingsi33 and i3 1 which'in turn are mounted on 'aihracket 355secured to ran upstandingscenterwall 36 integral on the :base 538. The control cam I6 is disposed horizontally, in the :plane .of Itheiintermittent shaft :Liand is located laterall-yifrom the axis of the shaft '3 so that its axisiwill .be intersected by the angularly extend ing axes of the bearing elements 14 and 15 as they :are respectively engaged by ?the 'cam and held'iin 'horizontal position, as will be hereafter :described.

' The driving pinion .l'll, for'theishaftl, is-located adjacent the crank end ofrtheshaft '1, on the inner side ;of the bearing 9, and is engaged by the driving gear H which is mounted fast on ithe .main power shaft 12. As shown, the power :shaft 12 is journaled'below therintermittent shaft 7 'hetweensuitablebearings 36 and 31'which'are respectively mounted on a Zbracket 38, secured to the upstanding wall 31 :iand in a :boss formed in the end wall 32, which iSUPDOI'tS the driving end "of the shaft 1. The-shaft 1 2 is idrivenr'from a suitable power source, not shown, -by means :of a gear 39 whichis mounted fast 0n :the shaft '12 between thcgear H andthe bearing 3-1. Preferably :thelpower-source ,is common "to all of the operating components (of the stator winding .ma-

chine in order to provide" a perfectly timedoperiational relationship between the said operating components.

.As shown the control cam E56 is driven from =.the1;power shaft 12, which drives the pinion 1e and the intermittent shaft '1, in order that a ,perfectly timed relationmay be had between the cam :16, and-shaft E and thegearl l. The driving connection betweenthe power shaft 12 and the cam :shaft 1! is provided by a "bevel ear 40,

:mounted on theinner end or" the shaft t2,-which *gear'meshes with another beveLgear .41 .mounted on the upper end of an intermediate vertically disposed shaft 42 journaled in a bearing 43supported .by the bracket :38. The shaft 42 carriesa gear 44 fast 011 its lower-end and this gear is meshed with a pinion-45 mounted fast on the bottom end of the control cam shaft ll.

The mechanism shown in Figs. 6,? and 8 also includes the span change .elements shown in the diagrammatic illustrationof Fig. l, and'as shown the. face cam 2 2, which .actuates :the :span-ch'ange rack shaft $21-25, disposed on a werticalzaxis at thenpposite end of the rassemblysfrom the =sp'an crarik $8. .The :camfiZ-is located substantiallyiin the :plane of the zintermittentvshatt with its axis intersecting ran :extension'of the axis 5 of :theshaft 1], and the shaft dfiywhich supports and drives the cam .22 2. i @mounted in vertically spaced bearings which are carried :by .a bracket 4:? secured on the :center wall'3fi. The .:shaft:46 is driven through bevel gears '48 and 59 from :a -d1 ive:shaft .5!) which in turn :is operated :at predetermined'interval's by control means, notshown, which form no part of .the :present invention.

. AsshOWIl in Figs. :1 0, l1 and :12 the intermittent control cam lfi isa cylindrical body formed with a peripheral channelor cam track 5| and atone side a segment of the :cam periphery is cut away to provide an axially extending opening '52 lead- Zing from end-to :end of the cam body. Thus'the :ca'mfitrack SiI'i is not continuous but'ratheris'an interrupted guidewayhaving an entrancefrom the cam body'opening 52at one end and an exit into th'e said :opening at the otherend, "as indicated by the arrows in Fig. 12. This control cam is intended to receive a cam iollower through ':the top end-o'fthe body opening 52 and into the leading end of the cam trackSl, hold thezoam follower in fixed position for a predetermined period, :and then to discharge the cam follower from the exit end of the oam track and through the bottom end of the body opening.

In the 'present'embodiment of the invention there ar two cam followers which consistof the bearing "elements M and t5, projecting laterally 'fromth'e control head lB-of the intfsrniitteIit-shaft 5 7. In the form shown each bearing element comprisesa roller .rotatably mounted on a'stub shaft which projects outwardly from "the control head i=3 along :an axis "inclined endwise of the shaft 1 at an angle of 60-degrees from the shaft axis. Each roller is Torm'ed with a spherical periphery and the rollers are disposed on -'diametrically opposite sides of the control head 3. 'Thusas the rollers or bearing-elements I4 and f5 gyra'te about the axis of the shaft Ipupon rotation of the same, the rollers' will he brought, successively, into operative engagement with the control cam.

'The control cam 1 6 is positioned so that the axis of -its drive shaft i"? is normal to a plane which includes the axis of the intermittent'shaft "I and also intersects an-element of the path of the gyrating axes of thebearing elements and I5; and the cam is so located that, whenits-axis is intersected by a bearingelement axis, the respective bearing element will extend' radially into andbe'fully engaged by thafiat-part of the-cam *trackEI'Whih is disposed wholly within the plane of the shaft Thus upon rotation-of the shaft 1 and the cam l6,-in properly timed relationpthe bearing elements 14 and 15 will be delivered successively into the cam track through the upper end "of th'e'cam =body opening '52 held' in fixed "position while=the cam revolves, "and finally be released =and=discharged downwardly through'the bottom-end of the-cam'body opening.

It' will nowbo seen that although the intermittent shaft I is driven by-a continuously rotating gearits own rotation-is'interrupted and the period of dwell or nonrotation is that-periodwhen a bearing element is engaged in the-flat portion of the cam track fil. 'Thisaction is madefpossible by interrupting the teeth of the pinion ,Ifl :at the diametrically. opposite locations which are tangential with the gear l'l when' the bearing ele- 1 1 ments 4'4 and H5, respectively, are engaged in the fiat portion of the cam track, so that the pinion ill is out of driving engagement, or out of mesh, with the gear H at those places.

Such an arrangement of the pinion teeth is shown in Fig. 9, and as shown four teeth are removed or omitted from each of diametrically opposite sides of the pinion it! so that at those points there is no engagement with the gear H. In this manner-the gear II and pinion ID are in driving engagement until one of the bearing elements is delivered into the flat portion of the control cam track 5!, at which point the gear and pinion teeth become disengaged. When the respective bearing element reaches the release end of the cam track it is delivered from' the'end of the cam with a turning movement about'the axis of the shaft 1 which rotates that shaft and causes the pinion teeth to again-mesh'with the rotating drive gear H, whereupon the shaft 1 is positively driven to the point where the next tooth gap in the pinion l occurs. This sub stantially half-turn'of the shaft I causes the sec-' ond bearing element to be delivered to the control cam i6, and the intermittent shaft 1 is again held fast against any angular or turning movement while the second bearing element passes through the flat portion of the cam track. a

The timing of the intermittent rotation of the shaft I, and the intermittent engagement or meshing of the pinion i0 and gear I l, is governed by the design of the control cam It. The angular length of the gapor peripheral opening 52 in the cam .body represents that period in the cycle of cam rotation during which the intermittent shaft is turned, by the drivinggear H'and the pinion 10, to bring the'next successive bearing element into engagement with the cam. The rise and fall of the cam track 5|, at the entering and leaving ends respectively, represent the periods of transition or transfer of intermittent shaft rotation or control from the gear H' to the cam and then from the cam to the gear ll. And the flat portion of the cam track represents the period in the cycle of cam rotation when the intermittent shaft is stopped and held fast. c

Thus, it will be seen, the speed of rotation of the control cam it determines the time interval when the intermittent shaft is stationary and the frequency of the intermittent movements of the shaft; and the angular length of the gap or body opening in the cam is determined-by the speed of rotation of the intermittent shaft 1 between dwell periods. For this last reason the driving speeds for the cam l6 and the intermittent shaft l' must be positively and accurately correlated.

A simple method of correlating the drives, for the control cam I6 and the intermittent-shaft 1-, is to drive both elements directly from acommon power source and this is the arrangement utilized in the specific embodi-nrients of this invention shown in Figs. 6, TI, 8 and 13 wherein :the drives for both the control cam IE and the intermittent shaft I are taken 'bydirect gearing from the power shaft !2.

A critical factor in the control cam design is the shape of the rise and fall portions of the cam track at the entering and leaving ends thereof where the bearing elements are received and discharged; Each bearing element is entered into the cam-while the intermittentshaft is being positively driven by the pinion Ill and gear II and it is in the entrance or rise portion of the cam track .that'the transitionof control of the intermittent shaft from the gears to the can;

takes place. Likewise it is in the exit or fall pore tion of the cam track where control of the intermittent shaft is transferred from the control cam to the intermittent shaft drive. Therefore, since the bearing elements gyrate in a plane parallel to the axis of the control cam and pass through the cam in the axial direction thereof; the rise of the cam surface must be shaped to receive the bearing element at the speed of 'r'ota tion of the pinion ID as it is driven by the gear ll pick up driving control of the bearing element as the last tooth preceding the: gap in the pinion l0 disengages from the gear H, and then bring the bearing element to rest in the flat of the cam track while more or less gradually absorbing the inertia of the intermittently moving parts. Also the fall of the camtrack must be shaped to re verse these operations and discharge the bear-'- ing element in such a manner that the pinion I0 is brought up to the pitch circle speed of the gear ll while the next pinion tooth, following the pinion-tooth gap, is caused to mesh precisely with the teeth of the running gear ll. 11

Referring particularly to Figs. 11 and 12 it wil be seen that the entrance or rise 53 of the cam track 5| in the control cam It follows a down-'- wardly curved path from the upper end of the body opening 52 to the flat portion 54. The curvature of this path is calculated, according to the speed of approach of the bearing element in relation to the speed of rotation of the cam, so that the bearing element will enter the cam path smoothly and' without shock. Also the exit or fall 55 of the cam track is downwardly curved toward the bottom-"end of the body opening and is calculated to start the 'gyratory movement of the bearing element, and hence rotation of the intermittent shaft, smoothly and with such timing and acceleration that the pinion ID will be brought into perfect meshing engagement with the gear H at the same pitch diameter speed. The method of calculating these cam paths will be readily understood by those skilled in the art.

As shown in Figs. 11 and 12' the cam track is made with upper and lower side walls, which are radial to the cam axis, and the side walls are angularly offset from each other. Also the curvatures of the upper and lower wall surfaces, at both the entrance and exit, are somewhat difier ent from each other. The reason i that the centerline of the'cam track iscalculated'with reference to the center of the bearing element, while the wall surfaces mu t be shaped to conform to'the annular shape of the bearing elements-at everyp'oint alongtheir path through the cam.

The upper and lower side walls are also spaced' apart a distance substantially equal to thediamlater of the bearing elements, with but a running clearance, in order that each 'bearing element will be positively'held against angular movement during the dwell period. This obviates overrunning and backlash in the intermittent mechanism.

In the particular cam shown in Fig. 11 the clear body opening, for entrance and exit of the bearing elements, extends through 66 degrees of the cam circumference. It is during the passage'of this space when control of the intermittent device is transferred from one bearing ele ment to the other. The bearing element enters the cam and becomes engaged at substantially the point A and the 14 degree offset of the upper and lower cam'track walls permits the bearing element to be engaged by the cam at diametrically opposite points. The bearing elementreaches the. pinion l have become meshedzwith. the.

gear I. land. the bearing; element. is:- releasedfrom. the: cam-.. The intermittent: shaft. is; then rotated by: the: gear i-:l,.-whilev the cam continues. to: untilthe next bearing element is: shifted. into the cam: track entrance? and the control-operation is repeated. ,The: speedof. rotation of the intermittent. shaft issuch. that thenext bearing, element is shifted. into; position to enter the camtrackv Whiieth-e cam. turns through. substantially the angular." extent of? the cam: body opening: and.

when-the bearing'element reaches thepoi-nt B the open portion of the pinion LB, where. the teeth are omitted, is tangential.- tothe gear II: and the pinion; is? completely released. fromthe gear. The. angular length and the axial extentof the riseand fall of the: cam track will, of course,

vary according to the number of teeth removed the pinion m to provide the: intermittent gaps.

- In: the specificv embodiment. of the invention shown. in. Fig. 13 the:- improved. intermittent device is utilized: to perform. the intermittent film transport; operation a motion picture: mech- The: arrangement of the intermittentelementsis: substantia'lly the same: as ini'Fig. 1 like numerals have been. used: to designate like parts; 56' designates the: film-5 guide assembly, havingtthe usual frameiopening; and: 51 designates the objective lens: system: The: film is driven through.- the: guide, assembly iii-by means of? a; sprocket-1&8 adapted and'i arranged; to en.- ga'ge the marginali feed. holes: of the strip as it passes throu h the guide. assembly The sprocket 58' isdriven by a pinioniifl, which in turn is driven intemnittently'by a: gear 5 9: mounted= fast on the intermittent shai't I. The power shaft I2 is' driven: by a handi cranks or: a suitable motor means in the 'usual' manner for operating motions picturemechanisms; and the? intermintent control device is operated thereby 'inz'the same manner as: has been. hereinbefore: described;

The main advantages of'z'this inventionreside inthe high degree of accuracy with which a predetermined intermittent motionican be trans;- mittedto anoperating mechanism; and? in; thetransmission. of such motion with a complete. absencaofi backlash or override in the. driven pa-rts: Other advantages. of the improved intermittent device; are. to. be found in; the fact that the driven mechanism is started and; stopped at. precisely predetermined points fnits-z operation, without shock orsl'ap, and with a-gradual acceleration and deceleration comparable with a simplehar inonic motion.

Further advantagesare to be-found the construction of the improved intermittent device whereby relatively heavy loads may be operated intermittently and at" high rates. of speed and frequency: and in the factthati the construction may be'made in substantially any size and is readilyadaptable to substantialy any situation 'in whfc'h an intermittent movement is desired.

' Although but one specific embodiment of this invention is herein shown and described it will be understood that numerous details of the con- 1 2 stnuction shown may be; altered or omitted. with:- out. departing from. the.- spirit of i this invention as defined by theiollowingv claims...

I claim:

1.; intermittent.- movement device comprising azcontinuouslyoperating driving means. amtatinga member havingv a driving connection withsaid driving means,. said driving connec tion' beingadapted to permit operation. of. said mean-s independently of said. rotating memben, aprojecting: bearing. element fixed. to saidi'rotating. member and offset laterally relative}to-- the axis thereof, a--. controi 'means independentiofi said driving connection adapted to engage: said bearing. element. at predetermined intervals.- and: hold said bearing element. in. fixed position for a. predetermined. period. means. to actuate-said control means in timed relationv with said drivingymeans and means on. said control means adapted to release said bearing. element atthe end of said. predetermined period for etfiecting driv ing operation of said rotating. member bysaid. driving: connections.

2'... An intermittent movement device" comprise ing: a: continuously. operating. driving. means. a rotating, member having. a'driving connection with said; driving means,v said driving. connection being adapted: to permit operation of said. driving means.- independently of said: rotating member,; ail-projecting bearing; element. fixed to. said rotating member and oifsetlaterally relativeto: the axis: thereof, a control. means: comprising av rotatablefbody disposed inthepath ot'saidbeari-ng element. and. having; a1 peripheralcam. track laying principally a. plane parallel. with the" axis: of

said: rotating? member, said. cam. track: being adapted. to receive said bearing; element; andhaving'f-an entrance" leading from one: end. of said bodyand. an: exit opening. to the opposite end of said body, and means to. drive saidbody in. timed relation with. said driving means.

3; An intermittent movement device comprisingi acontinuously operating: driving means, a rotating member having a driving connection with said driving. means. said; driving: connectiombeing adapted. to' permit operation of said driving meansindependently of said rotating member; a. projecting-bearing. elementfixed to said: rotating member." and offset laterally'relative to the axis thereof, a control means. comprising rotatable cylindrical body disposed with. its end margin intersecting the path of said bearing element.- and with. its axis at' right; angles to the axi'ssof said rotating member, said body having 1 a.-.peripheral: channelentering from one/end of thebody and leaving from the opposite endithereoi';said channelbeing adapted to receivez and discharge said bearing element in the axial direcitionof said. body and lying" principally-mettle planeofsaid rotating member, and. means to ro.-

tate said? body intimed relation-With said driving means.

4. An intermittent movement device comprising arotatable shaft having means thereon to transmit motion therefrom, a-continuously operating driving means having connection with said shaitfor rotating the same, said connection having a dwell portion to interrupt the rotation of saidshaft at predetermined intervals, a' bearing elementfixed to said shaft and disposedlatorally from the axis thereof, and a control means independent of said driving means operating in timed relation with the interruptions of the retat-ion of said shaft and adapted to engage said.

bearing element and hold the same stationary for 13 a predetermined period, said control means having means thereon for imparting angular movement directly to said bearing element at the end of said predetermined period.

5. An intermittent movement device comprising a rotatable shaft having means thereon to transmit motion therefrom, a pinion fast on said shaft, a continuously rotating gear positioned for driving engagement with said pinion, said pinion having a number of its teeth omitted to provide a peripheral space free of engagement with said gear, a bearing element fixed to said shaft in axially spaced relation to said pinion and disposed laterally from the axis thereof, and an independent control member driven in timed relation with said gear and positioned in the path of said bearing element, said control member having control means for engaging and holding said bearing element in fixed position for a predetermined period while said pinion is disengaged from said gear, said control means having a cam formation thereon adapted to release said bearing element and impart angular movement thereto at the end of said predetermined period.

6. An intermittent movement device comprising a rotatable shaft having means thereon to transmit motion therefrom, a pinion fast on said shaft, a continuously rotating gear positioned for driving engagement with said pinion, said pinion having a number of its teeth omitted to provide a. peripheral space free of engagement with said gear, a bearing element fixed to said shaft and disposed laterally from the axis thereof, and an independent control member driven in timed relation with said gear and positioned in the path of said bearing element, said control member having a cam means to engage and hold said bearing element in fixed position for a predetermined period while said pinion is disengaged from said gear, said cam means having a leaving end portion inclined to impart angular movement to said bearing element and rotate said shaft at the end of said predetermined period and thereby cause meshing engagement of said gear and pinion.

7. An intermittent movement device comprising a rotatable shaft having means thereon to transmit motion therefrom, a pinion fast on said shaft, a continuously rotating gear positioned for driving engagement with said pinion, said pinion having a number of its teeth omitted to provide a peripheral space free of engagement with said gear, a bearing element fixed to said shaft and disposed laterally from the axis thereof, a control means positioned in the path of said bearing element and adapted to engage and hold said bearing element for a predetermined period upon disengagement of said pinion and gear, means to operate said control means in timed relation with said gear, and means on said control means adapted to impart angular motion to said bearing element and cause meshing engagement of said pinion and gear at the end of said predetermined period, said last named means being adapted to release said bearing element when said pinion and gear become meshed.

8. An intermittent movement device comprising a rotatable shaft having means thereon to transmit motion therefrom, a pinion fast on said shaft, a continuously rotating gear positioned for driving engagement with said pinion, said pinion a peripheral space free of engagement with said gear, 'a bearing element fixed to said shaft and disposed laterally from the axis thereof, a rotatable cylindrical cam positioned with its end margin intersecting the path of said bearing element and disposed on an axis at right angles to the axis of said shaft, a peripheral channel on said cam lying principally in a plane parallel with said shaft axis and having an entrance from one end of said cam and an exit from the other end of the cam, said channel being formed to receive and release said bearing element in the axial direction of said cam, and the exit end of said channel being formed to impart angular motion to said bearing element in timed relation with said gear to cause meshing engagement thereof with said pinion, and means to rotate said cam at a predetermined speed.

9. In an intermittent driving mechanism, the combination with an intermittently driven shaft having a pinion thereon adapted and disposed to mesh with a continuously rotating driving gear, said pinion having a tooth gap of predetermined angular extent at which said pinion and gear are disengaged, of a control means comprising a hearing element projecting laterally from the shaft axis, a rotatable cam adapted and disposed to engage said bearing element during disengagement of said pinion and gear, and means to rotate said cam in timed relation with the rotation of said gear, said cam having a cam track formed to impart angular movement to said bearing element at a predetermined period in the cam rotation and cause meshing engagement of the pinion teeth with said gear.

10. In an intermittent driving mechanism, the combination with an intermittently driven shaft having a pinion thereon adapted and disposed to mesh with a continuously rotating driving gear, said pinion having a tooth gap of predetermined angular extent at which said pinion and gear are disengaged, of a control means comprising a bearing element projecting laterally from the shaft axis, a rotatable cam adapted and disposed to engage said bearing element during disengagement of said pinion and gear, and means to rotate said cam in timed relation with the rotation of said gear, said cam having a cam track formed to impart angular movement to said bearing element at a predetermined period in the cam rotation and cause meshing engagement of the pinion teeth with said gear at the peripheral speed thereof, and said cam being formed to release said bearing element when said pinion and gear are engaged.

THADDEUS F. HARVEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 316,797 Locke Apr. 28, 1895 980,371 White et a1. Jan. 3, 1911 1,129,754 Story Feb. 23, 1915 1,481,983 Brightman Jan. 29, 1924 1,559,970 Meahl Nov. 3, 1925 2,169,566 May Aug. 15, 1939 

